the.com/heat damage
the receipt for every straightener pass you swore was the last one.
means structural breakdown of hair's protein bonds from excess heat, leaving it dry, brittle, and unable to hold curl or shine.
from from thermal styling tools crossing 300°F, the point where keratin's hydrogen bonds break faster than they can reform, first widely studied as flat irons and blow dryers went mainstream in the 1990s.
breaking pointmost hair damages above 350 degrees fahrenheit
irreversibleno product repairs it, only prevents further loss
telltale signstraight ends that refuse to curl anymore